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Building Technologies Division
Basic documentation LMV36...
CC1P7544en
Infrastructure & Citiies Sector
13 Fan control
25.09.2013
13.10
Setting the parameters of the VSD
If a control signal of 95% (9.5 V) is not sufficient for the burner to deliver its rated
capacity, you can proceed as follows:
-
Set the maximum frequency to 105.3% of the motor’s rated speed
In the case of a motor frequency of 50 Hz, this means:
Set the maximum frequency of the VSD to 50 Hz x 1.053 = 52.6 Hz (on the VSD).
-
Then, standardize the speed (refer to chapter
Standardization of speed
)
There is no risk of motor overload since only 95% of the maximum control signal is
delivered during standardization and – later in operation – the effective speed is
controlled and monitored.
Frequencies of between 50 Hz and 52.6 Hz are delivered only if these are needed for
reaching the required speed due to increased output.
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Set the ramp times of the VSD according to chapter
Setting the ramp times